Option 1 “It highlights how the number and the complexity of the tasks that one must master to play an instrument spurs brain growth.” is the statement that best explains the idea that studying music can help develop the brain. In this paragraph, the focus is on how performing several tasks at the same time when playing an instrument help you develop certain skills such as coordination, muscular movement and senses awareness. By developing several skills both parts of the brain, right and left, are being exercised.
Option 2 is not correct as it does not identify which part of the brain is affected. Instead, it makes emphasis on how both parts are interconnected when studying music.
Option 3 is incorrect since the paragraph mentions a scientific source to back up the main idea, so it is mentioned as an example.
Option 4 is also incorrect as no direct relation is made in the paragraph between the effects of studying music and health improvement.